Seventy percent of people sleep on their side, but mummy bags are not designed to accommodate this. With a unique Spoon shape adding room at the elbows and knees, the Riff is a three-season down men's backpacking bag that is designed for side sleepers, and allows you to shift positions throughout the night.This popular bag is loaded with features, including Thermo Gills that help regulate temperature during the night, Blanket Fold that provides tucked-in comfort, and a waterproof/breathable footbox to withstand tent condensation. Zip together with the women's Jam(TM) for a double bag. This bag is a versatile superstar for everything from backpacking to car camping.Features:Spoon shape adds room at elbows and knees.Insulated with premium fluorocarbon-free, water-resistant Nikwax Hydrophobic Down.100% Responsible Down Standard (RDS) Certified.Waterproof/breathable footbox protects from tent condensation, keeping feet warm and dry.Blanket Fold external draft collar provides tucked-in comfort and temperature regulation.Thermo Gills allow you to vent body heat without letting cold drafts in.Full length double slider #5 YKK zipper with snag guard built into the draft tube makes getting in and out of the bag a breeze.Integrated pillow pocket allows a jacket, extra clothes, or a Fillo to be stuffed into the sleeve opening for a handy pillow-on-the-go.Video -Spoon Bags with Thermal Gills